Pressure-gage.



F. SCHUBERT.

PRESSURE GAGE.

APPLICATION FILED MAY 8, 1915.

1,1 92,574. Patented July 25, 1916.

Hil]- x \/10 ll/g INlENToR w s s 3 Frederick Schubert.

UNITED STATES PATENT OFFICE.

FREDERICK SCHUBERT, OF SELLERSVILLE, PENNSYLVANIA.

PRESSURE-GAGE.

Application filed May 8, 1915.

To all whom it may concern:

Be it known that I, FREDERICK SGHUBERT, a citizen of the United States, residing at Sellersville, in the county of Bucks and State of Pennsylvania, have invented certain new and useful Improvements in Pressure-Gages, of which the following is a specification.

My invention relates to pressure gages and it relates particularly to an improved form of gage whereby danger to the attendants through bursting of the pressure sensitive element will be reduced to a minimum.

To this end my invention contemplates an improved form of casing for the gage whereby in the event of rupture of the pressure sensitive element the casing, the dial plate or the glass will not be broken, and an outlet for the pressure within the casing will be provided at the rear thereof thus also obviating permanent damage to the other elements of the gage after the explosion has spent its force.

It should be understood that in many instances, for example, in the use of gages in connection with oxygen apparatus serious explosions occur due to carelessness in permitting oil to get into the apparatus. Various attempts have been made to obviate the danger resulting from such explosions, for

example, by placing a safety release in the back of the casing, but these devices have been more or less unsuccessful in practice. The explosions are so instantaneous and generate such sudden high pressures that all such devices as heretofore constructed have been entirely inadequate. In practice it has been found where such devices have been provided that both the safety back and the relatively light front structure of the gage are blown out simultaneously.

Heretofore pressure gages have been universally constructed with a cup shaped casiiig having its open side disposed to the front to receive the movement,,dial plate, and face glass. The solid Wall of the casing was disposed to the rear and no pressure resisting member was ever placed between the Bourdon tube or other pressure sensitive element and the indicating device and face glass.

My present invention contemplates the provision of a cup shaped casing, but with its strong substantial pressure resisting wall disposed toward the front and interposed between the pressure sensitive element and Specification of Letters Patent.

Patented July 25. 1916.

Serial No. 26,679.

the indicating device and face glass. While the rear side of the casing may be left open it is advisable, however, to provide a closure for the purpose of excluding dirt and dust. In order that such closure plate may function properly in conjunction with the strong substantial pressure resisting front wall this closure plate is preferably of a light construction and is lightly retained in the casing whereby the force from a rupture of the pressure sensitive element may be permitted to expend itself to the rear without appreciable resistance.

The nature and characteristic features of my invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part hereof, in which Figure 1 is a front elevation of a pressure gage embodying the main features of my present invention; Fig. 2 is a rear elevation thereof with the rear closure plate removed; and Fig. 3 is a vertical central section taken approximately on the line 3-3 of Fig. 2.

Referring to the drawings, in the particular embodiment of my invention therein shown, 5 is the gage casing of cup shaped conformation having a strong and substantial wall 6 disposed at the front side thereof and preferably formed integrally with the casing 5. Mounted within the casing 5 behind the wall 6 is the Bourdon tube 7 or other pressure sensitive element for controlling the indication of the pressure in the apparatus to which the gage is attached. This Bourdon tube or other pressure sensitive element is carried by a base block 8 secured to the casing 5 by means of screws 9 and this block 8 is provided with an integrally formed downwardly projecting nipple 10 having a threaded portion 11 and a non-circular portion 12 which extends through a complemental aperture in the easing at thelower part thereof. The non-circular portion 12 of the nipple 10 serves as a' portion of the nipple passing through the case were of circular cross-section.

The free end of the Bourdon tube opposite to that which is secured and connected with the base block 8 is pivotally connected to a link 13, the other end of which is also pivotally connected with an extending arm 14 of .a sector gear 15 which engages with a pinion 16 mounted on a shaft 17 which is journaled in the casing in any suitable manner. The shaft 17 extends through a bearing in the center of the strong and substantial wall 6 which is interposed between the gage mechanism and the face of the gage, so that said wall is sufficiently gas tight to prevent the transmission of pressure in the event of a rupture of the Bour don tube. On the outer end of the shaft 17 there is mounted the usual indicating needle 18 as clearly shown in Figs. 1 and 3 of the drawings. The scale of the pressure indications may be engraved directly on the front face of the Wall 6, but there is preferably provided the usual .thin metal dial plate 19 which may be fastened thereto by means of screws 20 or other suitable means. An externally threaded rim 21 extends forward from the casing 5 and there is mounted thereon a complementally threaded ring 22 which serves to hold and maintain in position the face glass 23 which protects the front face of the gage from dirt and atmospheric contamination.

Mounted internally in the rear of the gage casing is a coil spring 24 which is provided with an extending arm 25 which serves as a retaining means for holding in position a closure plate 26 which is provided to prevent the entrance of dirt into the mechanism of the gage. This closure plate is mounted in a recess 27 in the rear edge of the casing being more or less lightly retained therein by means of the tension of the spring 24 and its extending arm 25 which engages a clip 28 centrally mounted on the inner face of the closure plate 26.

It will be seen that With the arrangement as thus provided, in the event of a rupture of the Bourdon tube or other pressure sensitive element, the force of the escaping fluid will be resisted by the solid and substantial wall 6 interposed between said tube and the face glass and will be expended entirely to the rear causing the closure plate 26 to leave its seat in the recess 27 and permitting the pressure to thus escape and thereby obviating breakage of the glass or the casing and the consequent injury to persons in the neighborhood of the apparatus.

Having thus described the nature and characteristic features of my invention What I claim as new and desire to secure by Letters Patent is 1. In a single faced pressure gage, a cup shaped casing having its open side disposed to the rear and its strong substantial wall disposed to the front, indicating means disposed in front of said wall, a face glass mounted in front of said indicating means, and a pressure sensitive element mounted in the interior of said casing behind the said wall for controlling said indicating means, said wall being adapted to resist the force of rupture of the pressure sensitive element and to thereby prevent breakage of said glass.

In a single faced pressure gage, a cup shaped casing having its openside disposed to the rear and its strong'substantial wall disposed to the front, indicating means disposed in front of said wall, a face glass mounted in front of said indicating means, and a pressure sensitive element mounted in the interior of said casing behind the said wall for controlling said indicating means, said wall being adapted to resist the force of rupture of the pressure sensitive element and to thereby prevent breakage of said face glass, and a plate for closing the rear side of said casing lightly retained therein whereby the force of such rupture may be permitted to expend to the rear of the easing.

3. In a pressure gage, a casing, a pressure sensitive element mounted therein, a face glass mounted in the front of the easing, a strong substantial wall interposed between said pressure sensitive element and said face glass adapted to resist the force of a rupture of the pressure sensitive element and thereby prevent breakage of the face glass, and a plate for closing the rear of the casing lightly retained therein whereby the force of such rupture may be permitted to expend to the rear of the casing.

4. In a pressure gage, a cup shaped casing having a strong substantial wall disposed toward the front of the casing, indicating means disposed in front of said wall, a face glass mounted in front of said indicating means, a pressure sensitive element mounted in the interior of said casing behind said wall for controlling said indicating means, a plate for closing the rear of said casing, and spring means for lightly retaining said plate in position under normal conditions.

5. In a pressure gage, a cup shaped casing having a strong substantial wall disposed toward the front of the casing, indicating means disposed in front of said wall, a face glass mounted in front of said indicating means, a pressure sensitive element mounted in the interior of said casing behind said wall for controlling said indicating means, a plate for closing rear of said casing, and means for lightly retaining said plate in position under normal conditi ns comprising an internally arranged having an extending arm engaging said plate.

6. In a pressure gage, an integral cup shaped casing having its open side disposed a plate for closing said rear open side, and

to the rear, a plate for closing said rear open means for lightly retaining said plate in side, and means for lightly retaining said position under normal conditions comprisplate in position under normal conditions. ing an internally arranged coil spring hav- 7. In a pressure gage, a cup shaped casing an extending arm engaging said plate ing having its open side disposed to the at or near the center thereof.

rear, a plate for closing said rear open side, In testimony whereof, I have hereunto and means for lightly retaining said plate in signed my name in the presence of two witposition under normal conditions comprisnesses.

ing an internally arranged coil spring hav- FREDERICK SCHUBERT. ing an extending arm engaging said plate. Witnesses:

8. In a pressure gage, a cup shaped cas- ERNEST SHWIND,

ing having its open side disposed to the rear, A. G. DANNEHOWER. 

